Mechanisms of enhanced sesame protein recovery via cold plasma pretreatment: Impact of surface etching and oxidative hydrophilization.

Sesame cake, a by-product of oil production, remains underutilized despite its high protein content. Efficient protein recovery is essential for the valorization of this agro-industrial residue. This study investigated the efficacy of dielectric barrier discharge atmospheric cold plasma (DBD-ACP) pretreatment at varying voltages (25-45 V) on sesame protein extraction from defatted sesame flour (DSF). The extraction process followed a first-order one-term kinetic model. Results indicated that DBD-ACP pretreatment significantly increased protein dissolution and yield, achieving a maximum increase of 39.36% at 45 V. Structural analysis revealed that plasma treatment induced surface etching, resulting in increased porosity and roughness. Furthermore, the introduction of polar groups improved hydrophilicity, characterized by higher surface free energy and lower contact angles in the sesame protein fractions (SPFs). Consequently, these physicochemical modifications facilitated solvent penetration and intensified solid-liquid interactions. This study provided novel insights into the mechanisms by which DBD-ACP treatment enhances protein recovery, highlighting its potential as a sustainable technology for plant protein extraction.